Ribbon-vibrator



0. A. HOKANSON.

RIBBON VIBRATOR.

APPLICATION FILED MAR. I0. 1919.

1,383,540. Patented July 5, 1921.

2 SHEETS-SHEET I.

0. A. HO KANSON. RIBBON VIBRATOR.

APPLICATION FILED MAR. 10. 1919.

UNITED STATES PATENT OFFICE.

OTTO HOKANSON, OF WOODSTOCK, ILLINOIS, ASSIGNOR TO woons'rocx TYPE- RIBBON-VIBRATOR.

Sneciflcation of Letters Patent.

Patented July 5 1921.

Application filed March 10, 1919. Serial No. 281,740.

To all whom it may concern:

Be it known that I, O'rro A. HOKANSON, a

citizen of the United States, residing at Woodstock, in the county of McHenry and State of Illinois, have invented certain new and useful Improvements in Ribbon-Vibrators, of the following is a specification.

The invention has for its object the provision of mechanism of the class named which shall be of improved construction and operation.

The invention is exemplified in the combination and arrangement of parts shown in the accompanying drawings and described in the following specification, and it is more particularly pointed out in the appended claims.

In the drawings,

Figure 1 is a side elevation with parts 111 section, of a portion of the mechanism of a typewriter, showing one embodiment of the present invention.

Fig. 2 is a rear elevation of a portion of the mechanism shown in Fig. 1.

Figs. 3 and 4 are side and front elevations, respectively, of a hand lever for setting the mechanism shown in Figs. 1 and 2.

In visible writing typewriters, it is a well known expedient to provide mechanism for moving the ribbon in front of the platen at the time that the type bars are operated to make an impression, the ribbon being withdrawn after the impression has been made to permit the writing to be seen by the operator. It is desirable that mechanism of this kind shall be capable of adjustment to raise the ribbon to different heights so that different zones of the ribbon may be used and the vibrator mechanism of the present invention may be set so that a number of different zones of the ribbon may be employed at the will of the operator. A- ribbon of a single color may be employed, or the ribbon may be provided with different colored zones, if desired, and the mechanism may be .set to operate onthe different colors of the ribbon as the operator chooses. The top half of the ribbon, for instance, may be colored black or blue, or any color commonly used for ordinary work, and the lower part of the ribbon may be colored red or any other color used for s ecial purposes.

In the drawings, t e numeral 10 designates a portlon of a typewriter frame which has a key lever 11 pivotally mounted thereon and provided wlth a spring 12. A universal bar 13 1s pivotally. mounted at 14 and is moved downwardly whenever any one of the key levers 11 is depressed. The bar 13 is provided with an arm 15 which bears against a spring 16 to return the universal bar to its normal position after it has been depressed, and a stop screw 17 passes through an opening in a plate 18 on the end of the arm 15 to limit the movement of the unlversal bar 13 under the influence of the spring 16. A look nut 19 is provided on the screw 17 to hold it in adjusted positions. A screw 20 is threaded into the frame 10 and bears against the upper end of the spring 16 to adjust the tension of the universal bar. The screw 20 may be split, as shown at 21, and the halves sprung outwardly to produce sufiicient friction between the screw and the socket in which it is threaded to hold the screw in adjusted positions.

A platen shift rail 22 is supported by a frame having a bracket 23 pivotally carried by a bar 24 and a ribbon vibrator lever 25 is pivotally mounted at 26 on the shift rail frame. A ribbon carrier 27 is mounted on the outer end of the vibrator lever 25 and supports the ribbon 28 at its upper end. The vibrator lever 25 is swung upon its pivot 26 by a link 29 pivotally mounted at 30 on an oscillating member 31 pivotally mounted on a bolt 32 carried by a U-bar 33 which is supported on a bracket 34 secured to the typewriter frame. The oscillatory member 31 is normally held against a stop screw 35 threaded in a bar 36 projecting from the bracket 34, as shown in Figs. 1 and 2. The stop screw 35 is provided with a lock nut 37 for holding it in adjusted positions and a coil spring 38 connects the oscillating member 31 with the bar 36 for holding the oscillating member against the stop-screw. The oscillating member 31 is of irregular shape, as shown in Fig. 1, and is provided with a cam groove 39 in which a cam roller 40 is arranged to travel. The cam roller 40 is supported by a link 41 pivotally mounted at 42 at the upper end 0 a bell crank lever 43. The bell crank lever 43 is fixed the end of a shaft 44 which is journaled 1n the free end of the U-bar 33 and has its opposite end journaled in a bracket 45 extending downwardly from the typewriter frame. The lower arm of the bell crank lever 43 is provided with a pin 46 which proects into a second cam slot 47 in the oscillating member 31. The cam slot 47 is considerably wider than the diameter of the pin 46 to permit relative movement between the pin and sides of the slot for a purpose to be explained. A link 48 is secured to the cam roller 40 'on the side of the oscillating member 31 opposite the supporting link 41 for the roller. The lower end of the link 48 is secured to an upwardly projecting arm 49 connected with the universal bar 13, as clearly shown in Fig. 1.

When a key lever 11 is depressed with the parts in the position shown in Fig. .1, the arm 49 is moved to the right in Fig. 1, causing the link 48 to swing the cam roller 40 and its supporting link 41 about the pivotal support 42 of the link. This will cause the cam roller 40 to press downwardly on the lower face of the cam groove 39 and oscillate the member 31 in a clockwise direction about its pivot 32. As the member 31 is thus oscillated the link 29 will raise the ribbon vibrator lever 25 and lift the ribbon 28 into position to be struck by the type bar. The amount of movement of the ribbon is limited by the pin 46 which engages the upper edge of the-slot 47 and thus prevents overthrow of the ribbon. Where a two-color ribbon is used, this is desirable to avoid mixing of colors which might occur if the movement of the ribbon was not positively stopped at the same place each time. As soon as the universal bar 13 is released by the key lever 11, the spring 38 will return the oscillating member 31 to its initial position against the sto screw 35 and conseuently withdraw the ribbon 28 from in ront of the writing and to its normal position of rest.

The pivotal axis 42 of the link 41 may be y the shaft 44 and the bell crank lever 43, andj for this purpose the shaft 44 is provided, at

its end, with an arm 50 to the outer end of which a bar 51 is pivotally connected. The bar 51 extends to a position adjacent the front of a typewriter and is pivotally connected at its orward end, as shown in Fig. 3, to a segment plate 52 pivotally mounted at 53 on a bracket 54 carried on the upper plate 55 of the typewriter frame. The segment 52 is provided with a plurali? of notches 56 engaged by a spring catch 5 for holding the segment in different positions of adjustment about its pivotal support 53. A lever 58 is connected with the segment 52 and is provided with a finger piece 59 by means of which it may be swung to bring the various notches 56 into engagement with the spring catch 57. A pointer 60 is conneete with the lever 58 and may be brought to register with markings 61 on a casin plate 62 connected with the bracket 54. plvoted sto 63 is provided with a finger piece 64 an 1 may be swung into and out of the path of movement of the lever 58. The stop 63 is normally held in the path of the lever 58 by a spring 65 so that it 1s necessary to positively raise the finger piece 64 before the lever 58 may be moved into its extreme upper position.

he segment 52 is provided with notches corresponding to the positions of the pivotal support 42 for the link 41, represented by the lines a, b and a in Fig.1. The up-' permost position of the lever 58 corresponds to the position a in Fig. 1 of the drawings, while the lowermost position of the lever corresponds to the position a in Fig. 1 of the drawings. In the embodiment of the inventlon shown, the segment 52 is shown-as provided with a fourth notch to hold the producing any vibration of the member 31. w

This consequently is the stenciling position of the adjusting lever 58 for the ribbon vibrator and the typewriter may be operated when the lever is in this position without raising the ribbon into position to be struck by the type. In the stenciling position the pm 46 is very close to the upper edge of slot 47 to guard a ainst movement of the member 31 and rib on vibrator. When the lever 58 is shifted to move the pivot 42'into position b, it will be a parent that movement of the link 48 by the universal bar 13 will cause the roller 41 to press downwardly as it moves in the cam groove 39 and thus oscillate the member 31 about its axis 32 to raise the ribbon so that its upper portion will be struck by the type when a key is depressed. When the nut 42 is in the position b, the pin 46 wil be sition. If the lever 59 is further shifted to bring the pivot 42 into'position c, the

in 46 will bear downwardly upon the lower ace of the cam groove 47 and thus impart an initial rotation to the oscillatory member 31 in a clockwise direction as viewed in Fig. 1. This will raise the ribbon 28 so that its up r line. f a e is struck while the parts are in these positions, the cam roller 40 swin ing about its pivot 42 will press downward y upon the lower face of the cam groove 39 and operate the ribbon vibrator to raise the ribbon still more so that the type operated by the ke depressed will strike the lower portion 02 the ribbon which, in case of a parti-colored ribbon, would be the red band or zone. The cam grooves 39 and 47 are so related that the amount of movement imparted by the depression of the key is the same in both positions I) and o 'of the ivot 42, but the initial position of the ri bon in' position 0 is higher than the initial position when the. plvot is in the line b, so that different zones of the ribbon are used in the two positions althou h the amount of vibration is the same in 0th cases. The difl'erence in the zones employed is secured by the change in the initial position of the ribbon produced by the operation of the pm 46 which is set by the hand lever 59. It will be understood from this arrangement that although the device secures vis ble writing in operating in position b, the printing line will be covered y the upper portion of the ribbon when operating in position 0. The intermediate notch in the segment 52 between sitions b and 0 gives an intermediate initial position for the ribbon so that a different portion of the ribbon is struck by the type when a key is depressed from that struck in either positions I) or c. In this intermediate positlon the amount of vibration of theribbon is the same as in both positions 1) and a but the initial position of the ribben is intermediate the initial positions secured when the pivot is in positions I) and c.

It will thus be seen that the vibrating mechanism may be set so that the ribbon remains entirely below the printing line during the operation of the keys to permit the making of stencils.- A series of other adj ustments of the ribbon vibrating mechanism is provided sothat the ribbon is initially set by the adjusting mechanism at different initial ositions from which initial positions the rib n is raised a uniform amount for all positions of adjustment. Different zones of the ribbon will be used for the different adjustments of the ribbon shifting mechanism, the particular zone employed depending upon the initial position in which the ribbon is set by the adjusting mechanism and not upon any change in t e throw of the ortion will cover the printing and if desired markings can be ribbon produced by the operation of the key levers, for the reason that the throw produced by the key levers is always the same no matter what adjustment of the ribbon shifting mechanism is employed,.except, of course, the ad'ustment in which the ribbon is not vibrate at all but remains stationary for the purpose of making stencils. The constant throw of the ribbon vibrator for the different adjustments permits of uniform easy action of the key levers and avoids the heavy action that would be required to raise the lower edge of the ribbon into the printing line, if the movement began from the same normal position that it does when the upper portion of the ribbon is used. The fact that the writing is covered:,during the use of the lower ortion of the ribbon is of no practical disa vantage since this portion is used only for special purposes. This arrangement permits of smaller vibration than would be required to withdraw the ribbon entlrely from the printing line, and since it is desirable to have the key-lever action constant, this consideration affects not only the writing on the lower part of the ribbon but also on the upper part, because the same. amount of vibration is employed for both adjustments to' give uniform ke action.

Although the spring 38 ten s to return the member 31 and the ribbon vibrator 25 to their initial positions after a key has been struck, it will be understood that the spring 38 is not alone relied upon for returning the ribbon vibrator but is in fact more in the nature of a supplemental spring. The spring 16 for the universal bar 13, acting through the members 15, 49 and 48, is the prime mover in returning the ribbon to its retracted position so as to uncover the printing line when the top portion of the ribbon is being used, The tension of the spring 16 can be adjusted by the screw 10 placed upon the frame into which the screw 10 is inserted so that they will register with the slot of the screw to indicate the amount of the adjustment imparted to the screw. Since the universal bar 13 is operated by the key levers 11, it will be understood that the tension in the screw 16 will effect the key-lever tension during the part of the stroke subsequent to the engagement between the key levers and the universal bar. It is therefore desirable to provide means for adjusting the tension on the universal bar so that it may be readily set to suit the wishes of particular operators. The tension of the levers 11 during the first part of the lever stroke may be adjusted by changing the tension in the spring 12. During the first part of the stroke the keys will move easily under the touch of the operator, since the spring 12 is the only one opposing the movement during the beginnmg of the stroke. The spring 16 is the slot for sett next 'to come into action and after that the spring 38 is also moved by the operation of the key levers. This gives a gradually increasing resistance as the key moves downwardl and one which may be adjusted accor ing to the reference of the person operating the mac ine.

It will be seen from Fig. 1 that the end of the link 29, connected with the ribbon vibrator 25 is below the pivotal sup rt 30 for the opposite end of the link. en the platen shift rail 22 is moved from the full line to the broken line position in Fig. 1 the ribbon vibrator 25 moves upwardly with the platen carriage which raises the end of the link 29 connected with the vibrator lever 25.

As the link 29 rotates about the pivot 30 the end of. the link connected with the ribbon vibrator will move outwardly or to the right, as viewed in Fig. 1, thus swinging the vibrator about its pivotal support 26 and raising the ribbon a slight amount relative to the platen, In this way a different zone of the ribbon is brought into the writing line when the platen is shifted to change from lower to upper case letters.

I claim:

1. In a typewriter, a ribbon vibrator, an oscillatory member for operating said vibrator, means for operating said oscillatory -member toimpart movement to said vibrator, and a lever for simultaneously setting said oscillatory member in different initial positions and for adjusting the operating means for said oscillatory member to cause said oscillatory member to move uniform distances from said initial positions when a key-leveris operated.

2. In a typewriter, a ribbon vibrator, keylevers, an oscillatory member having a pair of cam tracks thereon, means operated by said key-levers and cooperating with one of said cam tracks for moving said oscillatory member, and means 0 erated independently of said key-levers an cooperating with theother of said camtracks for imparting a preliminary adjustment to said oscillatory member.

3. In a typewriter, a ribbon vibrator, an oscillatory member for operating said vibrator, said member having a pair of cam surfaces thereon, key-levers, means actuated by said key-levers and cooperating with one of said cam-surfaces for moving said oscillatory member to operate said ribbon vibrator, and means operated independently of said key-levers and cooperating with the otherof said cam-surfaces for s ifting said oscillatory member.

4. In combination, a ribbon vibrator, an oscillatory member for operating said vibrator, said member having a cam slot therein, and means cooperating with said cam saidoscillatory member in difierent initia positions and for limiting with respect to the link, an

said member to uniform movement from said different initial positions.

5. In a ribbon vibrator, the combination with an actuating member having a curved slot therein of an operating link therefor, a connection between the link and the member comprising a bearing pin which extends through the link and into the slot, nieans for varying the movement of the 'bearin pin in the slot comprisin an arm fixed to t e bearing pin and rotata le to various angular positions, and means for rotating the arm to various angular positions.

6. In a ribbon vibrator, the combination with an actuating member having a curved slot, of an operating link therefor, a bearing pin extendin through the link and into the slot, a rotata le shaft fixed in a position so that its axis coincides .with the axis of the bearing in in its normal position, means for rotatmgthe shaft, and a connection between the shaft and the bearing pin comprising two arms connected together at one end the other end of one arm being connected to the shaft and the other end of the other arm being connected to the bearing pin, the arm connected to the bearing pin belng rotatable to a point where it coincides with the axis of-curvature of said slot so that upon the movement of the o erating link the bearing pin will be swung idly in the slot about its arm as an axis without moving the actuating member.

7. In ribbon vibrator mechanism, an operating lever and a pivoted actuating member therefor, a connecting link pivoted to the latter, the operating lever having a curved slot engaged by a pin on the llnk, means to vary the movement of the pinin the slot comprising an arm pivoted to the pinned end of the link and settable at different angular positions with respect to the connectedend of the link.

8. In ribbon vibrator mechanism, an actuating member having an arcuate movement, a link pivoted at one end thereto, an arm pivoted at one end to the other end of the link, means to set the arm at different angular positions with res ect to the link and to swing about the en thereof opposite the link, and an operating lever having a curved slot engaged by the end of the link which is pivoted to said arm.

9. In a ribbon vibrator, an actuating member having an arcuate movement, a link pivoted at one end thereto, an arm pivoted at one end to the other end of the link, means to set the arm at difi'erent an lar positions an operating lever with a slot curved about an axis with a radius equal to the effective length of the arm to move the lever an amount varying with the distance of the other end of said arm from the axis of the slot.

10. In a ribbon vibrator, an arcuately movable member, a link pivoted at one end thereto, a pivoted operating member having a slot engaged by the other end of the link an arm pivoted at one end to this end of the llnk, and means for setting the arm in different angular positions comprising a rotatable shaft and an arm fixed thereto and connected at its outer end to the other end of the other arm.

In testimony whereof I have signed my 10 name to this specification on this 7th day of March, A. D. 1919.

OTTO A. HOKANSON. 

